Microwave Synthesis of Cu/Cu.sub.2O/SnO.sub.2 Composite with Improved Photocatalytic Ability Using SnCl.sub.4 as a Protector

Cu/Cu.sub.2O/SnO.sub.2 composites were successfully prepared with a facile microwave synthesis method. The structure of Cu/Cu.sub.2O/SnO.sub.2 composite was studied by morphology characterizations, such as X-ray diffraction, transmission electron microscopy and high-resolution transmission electron microscopy, which showed that the size of the Cu/Cu.sub.2O/SnO.sub.2 particles is 20-50 nm. The synthesis mechanism revealed that SnCl.sub.4 obstructed between Cu(OH) and ethylene glycol, preventing Cu(OH) being reduced into Cu at high temperature. The photocatalytic property of Cu/Cu.sub.2O/SnO.sub.2 composite was investigated by degrading the mixed dyestuff under the irradiation of visible light at room temperature. Benefiting from the effect of electron transfer, the photocatalytic performance of the microwave-prepared Cu/Cu.sub.2O/SnO.sub.2 composite was much better than that of pure Cu.sub.2O. The possible photocatalytic mechanism of the Cu/Cu.sub.2O/SnO.sub.2 composite catalysts was proposed and elaborated in this study. This synthesis of Cu/Cu.sub.2O/SnO.sub.2 composite may provide a method for other Cu.sub.2O/semiconductor composites microwave preparation.